A Northern Ireland academic has helped to answer the riddle of the death of more than 200,000 antelopes in the remote grassland of central Asia.

Scientists were baffled after the animals suddenly dropped dead in Kazakhstan in 2015.

Now it has emerged that the demise of the endangered saiga antelopes was caused by unusual environmental conditions.

Professor Eric Morgan from the Institute for Global Food Security at Queen's University was part of an international research team that uncovered what happened on the steppe.

He said: "These die-offs were devastating to the saiga antelope, and remind us of the need to support the conservation of large and healthy wildlife populations, able to survive such events."

Prof Morgan explained the research involved a large international team.

He added: "Although assembled around tragic events, it was encouraging to see that collaboration work so well, and to have Queen's play an important role in the investigation of a globally important disease event.

"In future, integrated consideration of environment, conservation and farming should become the standard for disease research."

The saiga antelope - a cousin to the springbok and gazelle - is on the cusp of extinction.

Over a period of just three weeks, entire herds of thousands of the healthy animals died of haemorrhagic septicaemia across the Betpak-Dala region of Kazakhstan - an area that is larger than Britain and Ireland combined.

The deaths were caused by Pasteurella multocida bacteria.

Researchers found many factors contributed to the extraordinary phenomenon.

In particular, climatic conditions such as increased humidity and raised air temperatures in the days before the deaths apparently triggered opportunistic bacterial invasion of the blood stream, causing blood poisoning.

The species' recent history suggests that die-offs are occurring more frequently, potentially making the antelopes more vulnerable to extinction.

This includes, most recently, losses of 60% of the unique, endemic Mongolian saiga sub-species in 2017 from a virus infection spilling over from livestock.

High levels of poaching since the 1990s have also been a major factor in depleting numbers, while increasing levels of infrastructure development - like railways, roads and fences - threaten to fragment their habitat and interfere with their migrations.

With all these threats, it is possible that another mass die-off from disease could reduce numbers to a level where recovery is no longer possible.